Streptococcal antibody: as an indicator of tonsillectomy.

The significance of antibody for streptolysin-O concerning tonsillectomy was studied. The results obtained were as follows. 1. The upper limit of ASO titer in 5,121 school children was 250 u and a value of more than 333 u was considered abnormal. But the level of the normal limit was different from year to year. 2. Among 143 cases with a high ASO titer of more than 833 u, only 12 cases had recurrent tonsillitis. There was no correlation between the tonsillar hypertrophy and the height of streptococcal antibodies. 3. There was a correlation between the titers determined by ELISA IgG-ASO and ASO in Todd units (r = 0.69), but there was no agreement between the titers determined by ELISA IgM-ASO and ASO in Todd units. 4. IgM-ASO determined by ELISA showed high levels in cases with early stages of streptococcal infection, focal infection and streptococcal carriers. Cases with high ASO, both IgG- and IgM-subclasses, were considered to have an indicative factor for tonsillectomy.